There's another connection, too: when Laurence Olivier made his famous film of Henry V, his historical advisor was Sir James Mann - former curator at the Wallace Collection. The 1944 film has created the most famous images of the battle (but also helped cement some of Shakespeare's most enduring mythology about it, as well as adding a few extras).

The Sinews of War: Arms and Armour in the Age of Agincourtis small but packed full of information and enlightenment. Prominent among the myths it dispels is that the armour worn was so heavy that knights could barely move. In fact, it weighed between 20-35kg: that sounds a lot, but 20kg is pretty comfortable when worn on the body, and even 35kg isn't an issue if you're a fit, strong soldier. You could certainly still mount a horse, and wouldn't need a crane to get onto it! (Mann ensured Olivier knew this ... which is why in the film, it's a French knight who is craned onto horseback.)

Current curator Tobias Capwell understands these things better than most: as well as his academic knowledge of the period's armour, he has practical experience thanks to having ridden in armour - and jousted - extensively. He busted some more myths at an Agincourt-themed evening organised by London Calling: the English were outnumbered by the French, but not nearly as heavily as Shakespeare suggested; it wasn't a victory against the odds as, numbers aside, most factors were in Henry's favour; the English army was not exhausted; and no one fighting in the battle was simultaneously suffering from dysentry!

The exhibition surprises in other ways. The chivalric ethos could be very different to modern ideals, so we have the jarring sight of a pair of gauntlets engraved with the word 'love'. It is not partnered with 'hate' in a mediaeval equivalent to knuckle tattoos, but repeated as an expression of what inspired knights in battle.

A tour of the permanent collections brought more discoveries.The biggest is that the displays are virtually unchanged since 1908, making them a museum of a museum. They represent two collections - of the comte de Nieuwerkerke, Napoleon III's Director of Fine Arts, and of Sir Samuel Rush Meyrick - both purchased by Sir Richard Wallace in 1871. Almost all the pieces in these displays were made for fighting rather than display - even an extraordinarily elaborate dragon's-head helmet.

The Sinews of War runs until 31 December 2015; admission to it and the rest of the Wallace Collection is free.